eskimo uses 3 gear box speeds, 49-1, 30-1 and 25-1. if you can find the engines speed you can do the math. Some i know off the top of my head.
hc-40 early 10 inch used the 49-1. 8 inch and all later 10 inch got the 30-1 gearbox so 300 rpm at the shaft. the newer p1 gets a 25-1 and those are smoking fast augers.
the m43- i know they list 30-1 on the specs but i know for a fact some got 25-1 gearboxes. 266 and 320 rpm respectivly.
strikemaster 40v- 300 rpm
ion g2 325 rpm.
trophy strike made them at 300 and 375 rpm.
the old model 30 turned at 475 or 500 rpm.
of course these are no load rpm figures. Under load they will drop some.
i have a milwaukee gen 3 fuel on an 8 inch pistol bit. 500 rpm in low gear. i have drilled side by side with a ion g2. The milwaukee holds more rpm( if the g2 is doing 325 the milwaukee is doing 350), but not a lot more under load, however you cant load up the drill as much as you can the g2. the gs was faster on every hole by a second or 2, no more. 27 inches of ice that day.